Sewer pipe cutting mechanism



March 6, 1951 J. .f CHILD, JR 2,544,254

SEWER PIPE CUTTING MECHANISM v Filed March 17, 1948 is formed with a keyway 34 into which extends a key rigid with the flanged sleeve bearing 2|. This enables the shaft to shift vertically without disturbing the driving connection to the knife holder 23.

On the extreme lower end of the drive shaft 22 is xed another keyed holder arm 35 to which is pivoted a knife 36 which operates in the same manner as the knife 24, i. e. in one direction of rotation of the shaft 22, the knife is thrown outwardly by centrifugal force to its operative position, but rotation of the shaft 22 in the opposite direction causes the knife to retract to its inoperative position.

Mounted on the table post I9 is a collar 31 arranged at the desired position beneath the table l1. On the collar is a contact 38 which is adapted to engage a projection 39 at the inner end of the lever arm 32. The projection 39 is normally in position to be engaged by the contact 38 when the table post I9 moves downwardly.

In operation, as above described, the table is first disposed in its uppermost position in engagement with the under face of the female bell die I6. After the bell is formed, the sewer pipe body is gradually formed and the table Il moves downwardly until the contact 38 engages the projection 39 thereby rocking the lever arm 32 in a clockwise direction which, through the link 3l and lever 29, moves the shaft 22 downwardly. This downward movement continues to a predetermined point at which the knife holder 35 is positioned at the proper point above the table l1, thereby predetermining the length of the sewer pipe. Upon rotating the shaft 2l in the desired direction, both knife holder arms 23 and 35 are rotated to cause the knife blades to be swung outwardly by centrifugal force thereby severing the walls of the pipe in the region directly above the female bell die I6 and also a proper distance below, thus excising a section of the tube which can be discarded or returned to the chamber I9 for reworking. During this operation contact 38 holds the lever 32 down while the two cutters are operated. Manifestly, the table I1 can then be moved upwardly to commence the formation of another sewer pipe length, the bell die having been freed of material. It will also be understood that by reversing the direction of rotation of the shaft 21 and accordingly the drive shaft 22, the knives are returned to their retracted or inoperative position and the knife holder 35 will be moved upwardly to lie within the male bell die member I8 during the start of the pipe forming operation. In this operation contact 38 will be moved upward out of engagement with the projection 39, allowing return of lever 32 to normal position. The weight of thelink 3| is such as to cause the return of these parts automatically so that the projection 39 will be properly positioned for the next downward movement of the table post.

It is to be understood that numerous changes in details of construction, arrangement and operation may be effected without departing from the spirit of the invention especially as defined in the appended claims.

What I claim is:

l. Sewer pipe cutting mechanism comprising a die for forming sewer pipe, female belldie part `adjacent the outlet end of said die, pipe cutting mechanism comprising a pair of vertically spaced rotary coaxial cutting knives, each being movable outwardlyby centrifugal force to operativepositionyupon'rotation in one direction and inwardly to inoperative position upon rotation in the opposite direction, a stationary mounting for one knife adjacent the outer end of said female die part, a mounting for the other knife enabling axial shifting movement in directions toward and away from said first knife, a pipe supporting table, a male die on said table movable into position relative to said female bell die to form the sewer pipe bell, a mounting for said table enabling movement thereof away from said female bell die part as the sewer pipe is formed, actuating mechanism responsive to movement of said table during the latter part of its movement for imparting shifting movement to said shiftable knife for operatively positioning same for severing in cooperation with said rst knife a pipe section in order to leave said female bell die part free for the next forming operation, and a conjoint drive for said knives.

2. Sewer pipe cutting mechanism comprising a die for forming sewer pipe, female bell die part adjacent the outlet end of said die, pipe cutting mechanism comprising a pair of vertically spaced rotary coaxial cutting knives, each being movable outwardly by centrifugal force to operative position upon rotation in one direction and inwardly to inoperative position upon rotation in the opposite direction, a stationary mounting for one knife adjacent the outer end of said female die part, a mounting for the other knife enabling axial shifting movement in directions toward and away from said rst knife, a pipe supporting table, a male die on said table movable into position relative to said female bell die to form the sewer pipe bell, a mounting for said table enabling movement thereof away from said female bell die part as the sewer pipe is formed, an' articulated actuating device responsive to movement of said table at a predetermined point in its movement for positively shifting said shiftable knife within the formed sewer pipe to desired cutting position, and a common drive for said knives.

3. Sewer pipe cutting mechanism comprising a die for forming sewer pipe, female bell die part adjacent the outlet end of said die, pipe cutting mechanism comprising a pair of vertically spaced rotary coaxial cutting knives, each being movable outwardly by centrifugal force to operative position upon rotation in one direction and inwardly to inoperative position upon rotation in the opposite direction, a stationary mounting for one knife adjacent the outer end of said female die part, a mounting for the other knife enabling axial shifting movement in directions toward and away from said first knife, a pipe supporting table, a male die on said table movable into position relative to said female bell die to form the sewer pipe bell, a mounting for said table enabling movement thereof away from said female bell die part as the sewer pipe is formed, link and lever mechanism for shifting said shiftable knife to the desired cutting position a predetermined distance beyond said female bell die part, an element responsive to movement of said table mounting for actuating said link and lever mechanism, and drive means for said cutting knives.

4. Sewer pipe cutting mechanism comprising a die for forming sewer pipe, female bell die part adjacent the outlet end of said die, pipe cutting mechanism comprising a pair of vertically spaced rotary coaxial cutting knives, each being movable outwardly by centrifugal force to operative position upon rotation in one direction and inwardly to inoperative position upon rotation in the opposite direction, a stationary mounting for one knife adjacent the outer end of said female die part, a mounting for the other knife enabling axial shifting movement in directions toward and away from said first knife, a pipe supporting table, a male die on said table movable into position relative to said female bell die to form the sewer pipe bell, a mounting for said table enabling movement thereof away from said female bell die part as the sewer pipe is formed, a drive shaft common to said cutting knives, a mounting for said shaft enabling axial movement, a lost motion drive connection between said shaft and said first knife, a lever for shifting said drive shaft, a lever arranged beneath said table, a link connecting said levers, and means movable with said table and engageable with said second lever for rocking same to effect axial shifting of said drive shaft.

5. Sewer pipe cutting mechanism comprising a die for forming sewer pipe, female bell die part adjacent the outlet end of said die, pipe cutting mechanism comprising a pair of vertically spaced rotary coaxial cutting knives, each being movable outwardly by centrifugal force to operative position upon rotation in one direction and inwardly to inoperative position upon rotation in the opposite direction, a stationary mounting for one knife adjacent the outer end of said female die part, a mounting for the other knife enabling axial shifting movement in directions toward and away from said first knife, a pipe supporting table, a male die on said table movable into position relative to said female bell die to form the sewer pipe bell, a vertically movable post supporting the table at its upper end, a collar on said post spaced below said table, link and lever mechanism for shifting said shiftable knife to position of use and having a part engageable by said collar so that upon continued downward movement of said post said mechanism is actuated, and a common drive for said knives.

JAMES L. CHILD, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 85,490 Stotz et al Dec. 29, 1868 272,727 Lyle Feb. 20, 1883 526,274 Wallace Sept. 18, 1894 FOREIGN PATENTS Number Country Date 4,915 Germany May 2, 1879 20,007 Switzerland 1899 

